Originally Posted by ChickenHouse
AFAIK commercial operations is not permitted IFR SEP in EASAland, but I positively know that i.e. local German regulations require a 2-crew for private D-reg IFR SEP, in case the aircraft is not equipped with a 2-axis autopilot and altitude hold.
Well, yes and no, ChickenHouse.
The German regulations do require a 2nd person, but only specify that person needs to be authorized to operate the radio in English. It's not actually required they hold a pilot licence. Calling it "2-crew" (and logging it as such) is therefore rather dubious and probably unjustifiable.
The details are in LuftBO § 32 Zusammensetzung der Flugbesatzung.